1 /* 2 * Dropbear - a SSH2 server 3 * 4 * Copyright (c) 2002,2003 Matt Johnston 5 * All rights reserved. 6 * 7 * Permission is hereby granted, free of charge, to any person obtaining a copy 8 * of this software and associated documentation files (the "Software"), to deal 9 * in the Software without restriction, including without limitation the rights 10 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell 11 * copies of the Software, and to permit persons to whom the Software is 12 * furnished to do so, subject to the following conditions: 13 * 14 * The above copyright notice and this permission notice shall be included in 15 * all copies or substantial portions of the Software. 16 * 17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 18 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 19 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 20 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 21 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 22 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE 23 * SOFTWARE. */ 24 25 #include "includes.h" 26 #include "dbutil.h" 27 #include "queue.h" 28 29 void initqueue(struct Queue* queue) { 30 31 queue->head = NULL; 32 queue->tail = NULL; 33 queue->count = 0; 34 } 35 36 int isempty(struct Queue* queue) { 37 38 return (queue->head == NULL); 39 } 40 41 void* dequeue(struct Queue* queue) { 42 43 void* ret; 44 struct Link* oldhead; 45 dropbear_assert(!isempty(queue)); 46 47 ret = queue->head->item; 48 oldhead = queue->head; 49 50 if (oldhead->link != NULL) { 51 queue->head = oldhead->link; 52 } else { 53 queue->head = NULL; 54 queue->tail = NULL; 55 TRACE(("empty queue dequeing")) 56 } 57 58 m_free(oldhead); 59 queue->count--; 60 return ret; 61 } 62 63 void *examine(struct Queue* queue) { 64 65 dropbear_assert(!isempty(queue)); 66 return queue->head->item; 67 } 68 69 void enqueue(struct Queue* queue, void* item) { 70 71 struct Link* newlink; 72 73 TRACE(("enter enqueue")) 74 newlink = (struct Link*)m_malloc(sizeof(struct Link)); 75 76 newlink->item = item; 77 newlink->link = NULL; 78 79 if (queue->tail != NULL) { 80 queue->tail->link = newlink; 81 } 82 queue->tail = newlink; 83 84 if (queue->head == NULL) { 85 queue->head = newlink; 86 } 87 queue->count++; 88 TRACE(("leave enqueue")) 89 } 90
